The present invention relates to a safety belt arrangement, for use in land vehicles or aircraft for securing the occupants thereof, having at least one belt reeling device with a self-locking blocking mechanism with mechanical control means for moving a locking member into the blocking position which prevents the belt from being pulled out further.
As is well known, safety belt arrangements for the occupants of land vehicles and aircraft make use of safety belt reeling devices which prevent the belt from being pulled out further in the event of actuation. In order to control a movably mounted locking member in the blocking position thereof, the belt reeling devices have mechanical control means which respond both when the belt is pulled out too quickly and when acceleration or deceleration occurs which exceeds a limit set by the manufacturer, thus moving the locking member into its blocking position. The operating principle of a belt reeling device of this kind is described, for example, in U.S. Pat. No. 4,615,540, Sedlmayr et al, for use in motor vehicles. However, in terms of the operating principle, there is no fundamental difference between belt reeling devices for motor vehicles and those for aircraft.
A safety belt arrangement of this kind has the disadvantage that the mechanical control means of the belt reeling device in question can only ever respond after certain movements have been performed by the strapped-in occupant of the vehicle or by the vehicle itself, which means that there is necessarily a time delay between the moment of the cause of the emergency and the prevention of further withdrawal of the belt, with the consequence that before reaching their blocking position the belt reeling devices will still release some belt, so that the strapped-in occupant of the vehicle can be subjected to a forward movement.
In safety belt arrangements for aircraft, in particular, there is the problem that negative acceleration, such as may occur when the aircraft suddenly drops, cannot be detected by the mechanical control means of conventional belt reeling devices.
It is an object of the present invention to do away with a response time caused by the system in a safety belt arrangement of the kind mentioned above and thus further improve the safety of the strapped-in occupant.